Wrapping paper



Patented May 10, 1938 UNITED STATES PATENT OFFICE WRAPPING PAPER No Drawing.

Application June 28, 1937,

Serial N0. 150,755

Claims.

This invention relates to prevention of rancidity in wrapping paper for foods, particularly meats.

Hitherto great difficulty has been experienced 5 in eliminating a rancid odor which develops in wrapping paper for meats, fish and the like, the paper being impregnated with petroleum derived materials normally tending to become rancid.

According to the invention rancidity can be eliminated by adding a ligneous rancidity inhibiting agent to the usual stock from which the paper is made such as suiphite pulp, bleached or unbleached, and bleached or unbleached kraft pulp. It has been found advantageous, for example, to add from 1 to 10% of chemically untreated groundwood pulp to the pulp furnish used for making the wrapper. For example, 10% of spruce groundwood pulp is added to unbleached sulphite and a sheet is formed from this stock on the paper machine. A 32-lb. (241(36-480) basis weight sheet so made is treated with petrolatum or other water-proofing material until the body of the sheet is thoroughly saturated producing a finished weight of the sheet of approximately 40-lb. (2ix364=80) basis weight. This sheet will show no free petrolatum on the sheet surface and is particularly adapted for use as a Wrapper for raw meats. It is characterized by a fair degree of resistance to the penetration by meat juices and fats and has considerable strength when wetted by the meat.

Wrapping paper made in accordance with this invention will not develop any rancid or objectionable odor over long periods of time. The

exact mechanism is not known which is responsible for inhibiting rancidity of petrolatum, parafiin waxes, mineral oils, or other waterproofing ingredients contained in the paper which normally turn rancid after a lapse of time. The 5 added ligneous material appears to contain an agent which inhibits the rancidity of the waterproofing materials.

I claim:

-1. Rancid-proof wrapping paper consisting of 10 a sheet of paper treated with petrolatum, said sheet containing 1 to 10 per cent groundwood to retard rancidity.'

2. Rancid-proof wrapping paper consisting oi a sheet made of unbleached sulphite pulp treated 15 with petrolatum, said sheet containing 1 to 10% groundwood pulp to retard rancidity.

3. Rancid-proof wrapping paper consisting of a sheet of paper treated with a petroleumderived water-proofing substance tending to be- 20 come rancid, said sheet containing 1 to 10 per cent groundwood to retard rancidity.

4. Rancid-proof wrapping paper consisting of a sheet of paper treated with a petroleum-derived water-proofing substance tending to become rancid, said sheet consisting of unbleached sul-= phite pulp and 1 to 10% groundwood to retard rancidity.

5. Rancid-proof wrapping paper consisting of a sheet made of unbleached sulphite pulp treated with petrolatum, said sheet containing 1 to 10% spruce groundwood pulp to retard rancidity.

GEORGE J. BRABENDER. 

